CartoDB/cartodb20

/**
 * A collection that holds a set of organization groups
 */
cdb.admin.OrganizationGroups = Backbone.Collection.extend({

  model: cdb.admin.Group,

  url: function(method) {
    var version = cdb.config.urlVersion('organizationGroups', method);
    return '/api/' + version + '/organization/' + this.organization.id + '/groups';
  },

  initialize: function(models, opts) {
    if (!opts.organization) throw new Error('organization is required');
    this.organization = opts.organization;
  },

  parse: function(response) {
    this.total_entries = response.total_entries;
    return response.groups;
  },

  // @return {Object} A instance of cdb.admin.Group. If group wasn't already present a new model with id and collection
  //  set will be returned, i.e. group.fetch() will be required to get the data or handle the err case (e.g. non-existing)
  newGroupById: function(id) {
    var group = this.get(id);
    if (!group) {
      group = new this.model({
        id: id
      });
      // collection set on model, but not added to collection yet
      group.collection = this;
    }
    return group;
  },

  // @return {Number, undefined} may be undefined until a first fetch is done
  totalCount: function() {
    return this.total_entries;
  }

});